THE OUTDOORS ALMANAC | EXPEDITION EXCERPT

Blown away

How Mt. Everest gets snowboarders off her back

The setup: Stephen Koch of Jackson, Wyo., wants to climb up and snowboard down the highest peaks on all seven continents, and has bagged six. Photographer Jimmy Chin, also of Jackson, is along to document his attempt, aided by Lakpa Dorje Sherpa and Kami Sherpa, to snowboard the Hornbein Couloir on the north face of Mt. Everest. It's Aug. 29, 2003.

After a month of acclimatizing and a six-hour slog through dense fog on a glacier, the climbers press onward at 20,000 feet, roped together in the dark, headlamps blazing, to the bottom of the north face. Nighttime is colder, the snow is frozen hard and thus safer. But the air is "warm." Chin, 29, has peeled his down suit like a banana. Having just heaved Lakpa from a crevasse where he had fallen chest-deep, the four throw down their packs and weigh their slow progress and the awaiting 9,000-foot ascent, without supplemental oxygen, of the Hornbein Couloir.

Then crack, the sound of mountain letting go. Chin hears Koch, his climbing partner, call to Lakpa, asking if the distant roar will reach them. "No," he answers calmly. But a wall of white mist hits their lights, the edge of an avalanche powered by "VW bus-size" ice chunks called seracs. Koch, Lakpa and Kami dive onto their packs. Chin stays put, facing the blast, because, "I thought we were going to get crushed." The pressure wave sweeps him off his feet, pitching him 25 feet to the end of his rope. His pack full of photography gear schusses 300 feet, skipping across the crevasses of Central Rongbuk Glacier.

Landing on his back, fine powder blanketing him, Chin waits for the blows of ice. Instead, the rumble fades, disappearing into the dark. Chin and the others dust off and return to an advance camp at 19,300 feet, a pair of tents pitched on a flat, rocky patch of the glacier's flank.

"You don't conquer Mt. Everest," Chin says. "She either allows you to come on and climb her or she doesn't." The team would reattempt the trek two weeks later, this time making it several thousand feet up the north face before fatigue and deep snow turned them back.